beta decay

American  

noun

Physics.

1. a radioactive process in which a beta particle is emitted from the nucleus of an atom, raising the atomic number of the atom by one if the particle is negatively charged, lowering it by one if positively charged.

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beta decay British  

noun

1. Also called: beta transformation.   beta process.  the radioactive transformation of an atomic nucleus accompanying the emission of an electron. It involves unit change of atomic number but none in mass number

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beta decay Scientific  

1. A form of radioactive decay caused by the weak nuclear force, in which a beta particle (electron or positron) is emitted.

2. ◆ In beta-minus decay, a neutron in an atomic nucleus decays into a proton, an electron, and an antineutrino. The electron and antineutrino are emitted from the nucleus, while the proton remains. The atomic number of the atom is thereby increased by 1. The decay of Carbon-14 into Nitrogen-14, a phenomenon useful in carbon dating, is an example of beta-minus decay.

3. ◆ In beta-plus decay, a proton in an atomic nucleus decays into a neutron, a positron, and a neutrino. The positron and neutrino are emitted from the nucleus, while the neutron remains. The atomic number of the atom is thereby reduced by 1. The decay of Carbon-10 to Boron-10 is an example of beta-plus decay.

4. See also W boson

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Etymology

Origin of beta decay

First recorded in 1930–35

Example Sentences

Along this pathway across the nuclide chart, a common sequence involves beta decay of the parent nucleus followed by the release of two neutrons.

From Science Daily • Mar. 13, 2026

"Every step we take to eliminate interfering radioactivity gets us closer to finding evidence for dark matter or neutrinoless double beta decay," said Saldanha.

From Science Daily • Sep. 21, 2023

They had a problem with beta decay, this nuclear reaction that seemed to have something missing.

From Scientific American • Jun. 7, 2023

Rarely, a proton in the oil will absorb an electron antineutrino to turn into a neutron while ejecting a positron—sort of the reverse of beta decay.

From Science Magazine • Jan. 11, 2023

This is different from beta decay, in which a neutron is transformed into a proton by the emission of an electron.

From "Big Science" by Michael Hiltzik